エレクトロンビーム法による鋼中介在物の分離と評価法の開発

抄録

In order to evaluate amount, size, shape and composition of Non-Metallic Inclusions (NMI) in metal quickly with high accuracy, an Electron Beam (EB) method was developed.
During melting of metal sample by EB, NMI floats on the top surface of the button-shape metal. Suitable irradiation energy which does not change the original form of NMI was made clear. The results by the present EB method were compared with those by conventional evaluation methods of NMI in metals, and this method was found equivalent to microscopic and oxygen analysis methods.
This method was applied to commercial grade steels, and it was found that the EB method was effective for various estimations in steel manufacturing, for example, for studying the effect of decrease of NMI during continuous casting, various phenomena by determining the size, shape and composition of NMI, and quality of ultra high purity metals. Especially, this method was of benefit to aluminum-killed steels.